Defending champions Real head into their UEFA Champions League quarter-final second leg without Karim Benzema, Luka Modric (both knee) and Gareth Bale (calf).
With the tie finely poised at 0-0 heading into Wednesday's meeting at the Santiago Bernabeu, Kroos says Real must not allow self-pity to creep in.
"It's not good to have so many key players injured, but there is no point complaining about it," he said.
"There is no doubt that Modric is an important player for the team but we have to focus on winning the game.
"We are very motivated. We had a good result in the first leg.
"Atletico have been difficult opponents for us but tomorrow we have the chance to beat them. Winning will be beautiful for us.
"We have to repeat our first-half performance in the first leg. However, we have to do it during the whole game this time.
"I am expecting a great atmosphere tomorrow at the Bernabeu, we need their support.
"Everybody knows Atletico - they have been very successful against us in recent matches.
"Our objective is to qualify for the semi-finals. We have to dominate the midfield, We will create chances if we manage to do so."
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